The invention relates to food products and, more particularly, to a method and apparatus for making cereal flakes. In particular, the invention relates to the making of flakes for ready-to-eat breakfast cereals by extruding and cutting cooked cereal dough.
A wide variety of food products are prepared from cooked cereal doughs, especially ready-to-eat (“RTE”) or breakfast cereals, as well as a variety of snack products. Generally in the preparation of the cooked cereal dough, cereal or farinaceous ingredients, such as various cereal flours, are first admixed with other dry ingredients such as salt, minerals, starch, sugars, to form a dry blend of ingredients and then is further blended with various liquid ingredients, including water, heated and worked to gelatinize or cook the starch fraction of the cereal ingredients and other starchy materials. A wide variety of blending, cooking and working apparatuses and techniques are well known.
More recently, the preparation of a cooked cereal dough using a cooker extruder, especially a twin screw extruder, has become commonplace. The cooked cereal doughs so prepared can be processed to form finished products of various size, textures and shapes. Typically, a post, cooked cereal dough formation step involves forming suitably sized and shaped individual pieces and drying to form finished cereal base pieces, such as shreds, flakes, biscuits or puffs. Thereafter, the finished dried cereal base pieces can have a topical coating applied to provide desired taste and texture attributes. For instance, in the preparation of a breakfast cereal, the topical coating can include a sugar coating.
Of particular interest to the invention is the making of flake-type ready-to-eat (RTE) cereal products. A typical production arrangement is illustrated in FIG. 1 wherein various ingredients, such as a grain-based ingredient, syrup and water 2, 4 and 6 are blended together and cooked in an initial extruder 15 to form a cooked cereal dough 18. The cereal dough 18 can undergo additional cooking, if desired, in a downstream cooking vessel 22, prior to being formed into individual pellets 28 in a pelletizer 32. The pellets 28 are then dried in a dryer 36 to establish dried pellets 40. Thereafter, the dried pellets 40, which can also be otherwise conditioned, are converted into thin wet flakes 44 in a flaking or flake forming step wherein the pellets are directed through flaking roller 48. Thereafter, the wet thin flakes 44 are dried and optionally puffed at 52 and/or toasted at 56 prior to reaching a final cooling zone 58 to produce a final flaked cereal product 60.
Although very effective, this method of producing cereal flakes includes numerous steps, each having associated manufacturing structure. To minimize this structure, it has also been proposed to form cereal flakes by forcing extruded cereal dough through a slotted die and, after extruding a desired length of the dough, the extrudate is cut and dried as represented by U.S. Patent Application Publication 2010/0055282. Although minimizing the structure needed to produce flakes, this arrangement has various disadvantages, in particular the inability to readily vary thicknesses of the flakes. With this known art in mind, there is seen to exist a need in the art for an apparatus and method to produce cereal flakes with minimal structure while still being able to readily vary flake thickness.